There are a lot of people that make the mistake of using many patterns and bright colors on their wall. If you are one of these people then you need to stop doing so immediately. You have to understand that you can either have patterns, or colors. What this means is that if you are using a mixture of patterns then you need to stick to a simpler color theme and if you are using more colors, minimize on the patterns a little.
The main reason why this is suggested is because this uncomplicated design plan will make you feel relaxed and stress free when you enter your home. On the other hand, using bright colors and pattern together make everything a little confusing and buzz like so you should stay away from them. Always remember the K.I.S.S (Keep It Simple Stupid) when you are designing your home.